Gold(I) Complexes Stabilized by Nine‐ and Ten‐Membered N‐Heterocyclic Carbene Ligands
作者:Alejandro Cervantes‐Reyes、Frank Rominger、Matthias Rudolph、A. Stephen K. Hashmi
DOI:10.1002/chem.201902458
日期:2019.9.6
N‐heterocyclic carbene (NHC) ligands have been developed and for the first time their gold(I) complexes were synthesized. The protonated NHC pro‐ligands 2 a–h were prepared by the reaction of readily available N,N′‐diarylformamidines with bis‐electrophilic building blocks, followed by anion exchange. In situ deprotonation of the tetrafluoroborates 2 a–h with tBuOK in the presence of AuCl(SMe2) provided fast
九元和十元 N 杂环卡宾 (NHC) 配体已经开发出来,并且首次合成了它们的金 (I) 配合物。质子化的 NHC 前配体2 a – h是通过容易获得的N , N'-二芳基甲脒与双亲电子结构单元反应,然后进行阴离子交换来制备的。在AuCl(SMe 2 ) 存在下,用t BuOK对四氟硼酸盐2 a – h进行原位去质子化,可以快速获得 NHC-gold(I) 配合物3 – 10。这些新的 NHC-金 (I) 配合物在环异构化反应中表现出非常好的催化活性(催化剂负载量为 0.1 mol%,转化率高达 100%),并且它们的固态结构揭示了金属原子周围的高空间位阻(% V bur up)到 53.0),这是由它们的扩展环架构引起的。